Thermoformed polymeric or thermoplastic containers are well known. The present invention relates to thermoplastic containers which are typically used for cold comestible products, such as salads or sandwiches. Such thermoplastic containers typically comprise a pair of generally transparent or opaque polymeric tray members which are hingedly connected along one side by a polymeric hinge. The hinge is constructed of the same material and thickness as the trays for allowing the trays to pivot with respect to each other between an open position and a closed position. The present invention also relates to an inexpensive semi-permanent package which can be reusable or disposable. That is, the semi-permanent package can be used for storing products for display or storage, such as jewelry, candy, etc.
The thermoplastic tray containers described above are problematic in that they lack rigidity or structural integrity, and, therefore, will often collapse or yield to the weight of the comestible product stored there within. It is difficult to achieve adequate rigidity and structural integrity in such containers without resorting to prohibitively expensive thick sections or ribs involving the use of relatively complex molds.
The hinge which allows the trays to pivot is also problematic. Since the hinge is constructed of the same material and thickness as the tray, it fatigues quickly and, therefore, has a limited life expectancy. As a result, such thermoplastic tray containers are normally used in a disposable manner. In addition, molding the hinge directly to both trays involves the use of more complex molds which increases the overall cost of such tray members.
As mentioned previously, the thermoplastic tray containers are pivotable with respect to each other between an open and a closed position; however, the means for locking the trays in the closed position is inadequate. Typically, such trays are locked in the closed position by a friction fit or a pair of cooperating lips, lugs or flanges. While such methods would appear to be adequate, more often than not the known thermoplastic containers unexpectantly pop open resulting in spillage and waste of the comestible product. This problem is usually resolved by wrapping rubber bands, tape or other external securement devices around the container. However, this is not an efficient solution to the problem and only serves to accentuate or highlight the problem.
Consequently, in the thermoplastic container field, there exists a need for a thermoplastic tray container which has a strong hinge connection and which provides additional rigidity over that permissible with current inexpensive disposable thermoplastic tray containers. There further exists a need for a locking or latching function which will secure the containers in the closed position.
The present invention provides a polymeric openable/closeable container having a frame for supporting a pair of tray members. The frame is constructed of a rigid plastic material and is adapted to receive a pair of thermoplastic tray members. The frame is constructed of a relatively rigid material for increasing the life span of the frame and includes a durable hinge member of the same material for allowing the tray members to pivot between an open and closed position. Furthermore, locking means is provided for securing the container in the closed position.
Consequently, the present invention overcomes many of the disadvantages inherent in the above-described thermoplastic tray containers by providing a rigid frame for increasing the containers rigidity and structural integrity. The frame of the present invention allows the thermoplastic tray members to be formed with a simple inexpensive mold, thereby reducing the manufacturing costs of such containers. Therefore, use of the present invention results in considerable savings in money as well as time for manufacturing and development.